Tổng hợp vật liệu tổ hợp nền Cu - nano Al 2O3 phân tán bằng phương pháp cơ hóa

Nguyễn Đức Duy và Đtg Tạp chí KHOA HỌC & CÔNG NGHỆ 139(09): 47 - 51

47

SYNTHESIS OF NANO Al2O3 DISPERSION - STRENGTHENED Cu MATRIX

COMPOSITE MATERIALS BY MECHANOCHEMICAL PROCESS

Nguyen Duc Duy1,2

, Tran Van Dung1

, Nguyen Dang Thuy1

, Ho Ky Thanh1,3*

1Ha Noi University of Science and Technology

2College of Mechanics and Metallurgy

3College of Technology - TNU

SUMMARY

Mechanochemical method was used to synthesize nano Al2O3 dispersion - strengthened Cu matrix

composite materials. Nanocomposite powders of Cu - Al2O3 were produced by milling at room

temperature in attritor mill using mixtures of CuO, Al and Cu powder ingredients. The

nanocomposite powders Cu - Al2O3 were cold pressed into briquettes and then conventionally

sintered at various temperatures (from 700C to 900C) and time (from 1 to 3 hours). The results

were analyzed by x-ray diffraction (XRD) and scanning electron microscope (SEM) with energy

dispersive spectrometer (EDS) showed that nano - sized Al2O3 ultrafine particles of about (50 ÷

100) nm was formed and uniformly dispersed into Cu matrix. The study results showed that the

effect of pressed - sintered parameters on microstructure and properties of composite Cu - nano

Al2O3 dispersed such as microstructure and density, hardness. Also, the results demonstrated that

nano Al2O3 can be able to synthesize by a mechanochemical process in attritor balls milling.

Keywords: mechanochemical, Cu-Al2O3, dispersion, X-ray diffraction, SEM, microstructure

INTRODUCTION*

Composites are materials consisting of two or

more components with different properties

and distinct boundaries between them.

Intensive research over the last two decades

has led to the emergence of composites as a

new class of engineering materials that

provide enhanced combination of high

temperature strength and acceptable levels of

ductility, toughness, fatigue resistance

required for a variety of applications. Metal

matrix composites (MMCs) are one of the

groups of such type of materials. Copper

based metal matrix composites are being used

in many industrial applications such as

contact supports, electrode materials for lead

wires, spot welding and others [1].

Dispersion strengthened Cu - Al2O3

composite materials are extensively used as

materials for products which require high￾strength and electrical properties, such as

electrode materials for lead wires and spot

welding, relay blades, contact supports that

require high strength at a high temperature,

*

Tel: 0984 194198, Email: [email protected]

wear-resistance for electrical discharge as

well as electrical properties and bearing

materials for industry [2]. Studies on the

synthesis and characterization of nano-scale

alumina dispersed copper metal matrix

composites have been attracting scientific

interest in recent years, since nanostructure￾type materials are expected to have special

physical and mechanical properties. In the

copper- alumina system, the nano-scale Al2O3

particulate dispersion provide unique

characteristics, such as high thermal and

electrical conductivities, as well as high

strength and excellent resistance to high

temperature annealing. The main requirement

for structure of dispersion strengthened

materials is homogeneous distribution of very

fine oxide paricles (dispersoids) in the copper

matrix [3,4]. In nanocrystalline materials, the

main role of the dispersoids is to limit grain

growth at elevated temperatures and to attain

a very small grain size, resulting in high

strength due to the fine-grain strengthening

mechanism [5].

In this study, Cu - Al2O3 nanocomposites

have been fabricated by mechanochemical